Triple-expansion mallet locomotive



1,629,370 Y May 1 s. M. VAUCLAIN TRIPLE EXPANSION MALLET LOCOMOTIVE Filed Nov. 25, 1925 i atented May 17, 1927. r

SAMUEL M. VA'UCLAIN, F ROSEMONT, PENNSYLVANIA, ASSiGNOR TO THE BALDWIN. LOCOMOTIVE WORKS, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION-OF PENNSYLVANIA.

TRIPLE-EXPANSION MALLET LOCOMOTIVE.

Application filed November One object of my invention is to construct a triple expansion locomot ve of the Mallet type, in which the boiler 18 rig dly secureo to the frame on which are mounted the intermediate cylinders and the high pressure cylinders.

In the accompanying drawing: Fig. l is a side View ofa Mallet triple expansion locomotive illustrating my invention; and v V V v Fig. 2 is an enlarged view showing the articulated joint between the two frames of the locomotive.

Referring to Fig. 1 of the drawing, 1 is the boiler, which is rigidly secured to the frame 2 of the locomotive. This frame 2 also carries the intermediate cylinders 3 and and the'higlrpressure cylinders 41:. The sad dles 3 and t' of these cylimlers are igidly secured to the boiler. The boi er is also supported by waist plates 55 and the rear structure 6 under the cab.

The forward end of the boiler overhangs the forward frame 7, which connected to the frame :2 by an articulated joint 8 of ordinary construction. This forward frame carries the low-pressure cylinders 17. Bearingblocks 9 on the boiler are arranged to slide on the supporting structure 10 on the forward frame 7.

On each frame are boxes for the axles 11, 11 and 11, on which are mounted the driving-wheels l2, l2 and 12*. These wheels of each frame are connected together and to the piston-rods in the ordinary manner.

This construction is omitted to avoid confusion.

high-pressure steam is taken from the steam'space of the boiler through the pipes 13 and 13 within the boiler and smoke-box, and through a pipe 13 ext-ending outside of the boiler to a pipe 13 connected to the hi ghpressure cylinders 4. v

The exhaust steam from the high-pressure cylinders 4 passes through av pipe 14 to the inlet passages of the valve-chests of the intermediate cylinders 3. I

The exhaust from the intermediate cyl- 25, 1925. Serial No. 71,407.

inders 3 passes througha pipe 15 which is connected to the exhaust pipes of the cylind-ers 3 by meansof a ball-joint. The pipe 15 extends to and communicates with a pipe 16 which leads to the steam inlet ports of the valve-chests of the low-pressure cylinders 17 on the forward frame 7. The exhaust passages of the cylinders 17 arecoupled to the nozzle 18 through a pipe 19, having a telescopic section which accommodates itself to the movement of the frame 7 in respect to the boiler.

lVhileI have shown in Fig; 1 each frame- The combination in a triple expansion:

locomotive of the Mallet type,- of a frame; a boiler to which" the frame is rigidly secured; forward-frame connected by an. articulated joint with the frame that supports the boiler, said boiler overhanging the said. forward frame; low-pressure cylinders mounted on the forward frame; intermediate cylinders mounted on the forward end of the frame that supports the boiler and high-pressure cylinders mounted at the rear of the intermediate cylinders on the :frame that supports the boiler; pipe connections between the boiler and the highrpressure cylinders, between the high-pressure cylinders and the intermediate cylinders, and between the iii-- TNT orricniy y termediate cylinders a-n'dthe louepressure cylinders; and an exhaust pipe connecting the low-pressure cylinders with a nozzle in;

the smoke-box of the boiler. 

